It really depends on the teacher and your ability to learn from that one person who is many levels beyond you.

For me, I always perfered to work out with my classmates under my teacher's direction because I felt I got more out of that experience. If that is not an option, then I think the only way for you to determine if this works for you is to try it.

I only think private lessons are worth teaching if the student is very sincere and they have some special circumstances, like they want to really do some swordword fundimentals training and get the feeling of a senior student being their partner - of if they have some injury and want to work through it with someone qualified to help them work out and stay safe given their odd body limitation. It takes an incredibly serious student to get me to do private lessons with them if they just don't have time for classes. I have not met too many of those students.